The published art is replete with examples of converting waste materials into useful hydrocarbon gases, liquids, and other carbon containing products. Early attempts at converting such materials to useful hydrocarbon gases, liquids and other carbon containing products included straight pyrolysis of such wastes.
Later studies led to the use of catalysts to enhance the breakdown of the waste materials. These thermal and/or catalytic assisted thermal cracking techniques were carried out under high temperatures and/or pressures, often entailing the use of temperatures in excess of 1500° F. and pressures in excess of 2,000 psi during the process. These conditions necessitated heavy equipment, and sometimes specialized equipment, to deal with the high temperatures and high pressures.
One such process can be found in U.S. Pat. No. 5,414,169, that issued to Takahashi, et al. on May 9, 1995 wherein there is disclosed a method of obtaining hydrocarbon oil from waste plastic material or waste rubber material, comprising the steps of subjecting the waste plastic material or a waste rubber material to thermal cracking so as to obtain a thermally cracked product, then liquefying the thermally cracked product into a liquefied product, and then causing a liquid phase cracking reaction of the liquefied product under the action of a catalyst on the liquefied product so as to produce a cracked product, and then cooling the cracked product so as to obtain the hydrocarbon oil.
U.S. Pat. No. 5,744,668, that issued on Apr. 28, 1998 to Zhou, et al., deals with a process of producing gasoline, diesel and carbon black with waste rubber and/or waste plastics. The process comprises pyrolysis, purifying, catalytic cracking and fractionation, similar to the '169 patent.
U.S. Pat. No. 6,270,630 that issued on Aug. 7, 2001 to Xing deals with a process and apparatus for producing hydrocarbons from residential trash or waste and/or organic waste materials, and deals primarily with the apparatus that is used for such process. The process requires that the organic waste materials are treated by a two-step cracking process, at different temperatures, with successive feeding and discharging.
There is disclosed in U.S. Pat. No. 6,653,517, that issued on Nov. 25, 2003 to Bullock, a method and apparatus for converting both organic and inorganic materials into more desirable products by the breaking down of these materials into their stable molecular constituents and reforming them into more desirable substances. The process involves the use of two chambers. Blended solid and fluid wastes are augured into the first chamber and agitated, preferably by rotating the chamber so that the waste tumbles over internal fins, while a heat gradient is applied. The process is catalyzed and the patentees use other means of enhancing the process.
U.S. Pat. No. 6,833,486, that issued on Dec. 21, 2004 to Nichols, et al, deals with a low energy method of pyrolysis of hydrocarbon materials such as rubber. In the process, the hydrocarbon material is heated while maintaining a vacuum using a clay catalyst. However, the catalyst is added to the feedstock of the process and is not put into the heated reactor prior to the introduction of the feedstock to the reactor as in the present invention.
A similar process can be found in U.S. Pat. No. 6,835,861, that issued Dec. 28, 2004 to Nichols, et al. in which the hydrocarbon materials is heated while maintaining a vacuum using a clay catalyst. This patent is a companion patent to the '486 patent. As in the '486 patent, the process requires that the hydrocarbon material and the catalyst be combined prior to feeding into the reaction chamber, and in column 4, line 65, to column 5, line 3, it is explained that the hydrocarbon material is added to the reactor first, then the clay catalyst, and the mixture is heated under vacuum conditions. In addition, at column 5, lines 28 to 30, it is disclosed that adding metals can be catalyzing certain reactions a augments the process.
A second patent to Bullock is U.S. Pat. No. 6,653,517, that issued on Nov. 25, 2003 that deals with a hydrocarbon conversion apparatus and method. The apparatus includes a pair of retort vessels in communication with each other, one of which has two chambers, one chamber containing a fluidized bed of catalytic feed and abrasive materials and the other a crusher mill. The vessels include lifting and stirring elements fixed to the interior walls to promote and help maintain a condition of fluidization of bed materials during operation. This process operates at negative pressure.
Finally, the patentees are aware of U.S. Pat. No. 6,210,562, that issued on April 3, to Xie, et al that deals with a process for production of ethylene and propylene by catalytic pyrolysis of heavy hydrocarbons. A pillared interlayered clay molecular sieve and/or phosphorous and aluminum or magnesium or calcium modified high silica zeolites are used as catalysts.